Method and apparatus for evaluating an airway status

Abstract

An airway status evaluation apparatus includes a respiration monitoring unit, a data processing unit, an inflation/deflation unit, and an inflation/deflation control unit. The data processing unit is electrically connected to the respiration monitoring unit, collects a respiration parameter of a patient from the respiration monitoring unit when a cuff meets an evaluation state, and evaluates an airway status of the patient according to the respiration parameter. The inflation/deflation control unit is connected to the inflation/deflation unit and controls the inflation/deflation unit to inflate and deflate the cuff so as to enable the cuff to meet an evaluation state. In the present disclosure, inflation and deflation of the cuff are implemented in a full-automatic or semi-automatic control manner, the respiration parameter can be automatically monitored, and the evaluation result is automatically calculated, thereby achieving the automatic evaluation for the airway status of a patient.

The invention claimed is: 
     
       1. An apparatus for evaluating an airway status of a patient prior to extubation of a tracheal tube, the apparatus is a plug-in unit electrically connected to a ventilator, comprising:
 an inflation/deflation unit comprising an interface connected to an inflation tube of the tracheal tube to inflate or deflate a cuff of the tracheal tube through the inflation tube; 
 a pressure sensor connected to the cuff to measure cuff pressure; 
 an inflation/deflation control unit, respectively connected to the inflation/deflation unit and a signal output end of the pressure sensor to control the inflation/deflation unit to inflate and deflate the cuff or to output prompt information about inflating or deflating the cuff such that the cuff is inflated to a predetermined pressure or completely deflated, and further electrically connected to the connection unit and communicating with the ventilator through the connection unit so as to receive an inflation/deflation instruction from the ventilator and/or feed back the cuff pressure to the ventilator; 
 a connection unit used to be in signal connection with the ventilator; and 
 a data processing unit electrically connected to a respiration monitoring unit which is used to monitor a respiration parameter of the patient; 
 after an automatic airway status evaluation procedure to evaluate an airway patency is started:
 the inflation/deflation control unit is configured to automatically inflate and deflate the cuff, and 
 the data processing unit is configured to automatically: collect the respiration parameter of the patient from the respiration monitoring unit until the cuff is inflated and deflated to meet an evaluation state, evaluate the airway status of the patient according to the collected respiration parameter to obtain an evaluation result of the airway patency, and output the evaluation result to indicate whether the extubation can be performed. 
 
 
     
     
       2. The apparatus of  claim 1 , wherein the inflation/deflation control unit controls the inflation/deflation unit to maintain the cuff to be at the predetermined pressure when the tracheal tube is in a normal ventilation mode, controls the inflation/deflation unit to completely deflate the cuff that is at the predetermined pressure after the automatic airway status evaluation procedure is started, and controls the inflation/deflation unit to inflate the cuff again to the predetermined pressure after the automatic airway status evaluation procedure is finished. 
     
     
       3. The apparatus of  claim 1 , wherein the inflation/deflation unit comprises an inflation/deflation device and a first interface, the inflation/deflation device is an air pump, a syringe, a proportional valve or an air evacuation valve, a power component of the inflation/deflation device is electrically connected to the inflation/deflation control unit, an air input/output port of the inflation/deflation device is connected to the first interface, and the first interface is connected to the inflation tube of the cuff. 
     
     
       4. The apparatus of  claim 1 , wherein the connection unit is a wireless communication unit or a connector for electrical contact through a conductor. 
     
     
       5. The apparatus of  claim 1 , wherein the tracheal tube comprises a catheter, the cuff surrounding an outer face of an end of the catheter, and the inflation tube having one end connected to an inside of the cuff, and another end used to introduce air to the cuff. 
     
     
       6. A ventilator, comprising:
 a breathing circuit, connected to an exposed end of a catheter of a tracheal tube, to provide a passage for a patient to inhale or exhale gas; 
 a respiration unit for providing mechanical ventilation for the patient, the respiration unit being connected to the breathing circuit; 
 a respiration monitoring unit connected to the breathing circuit to monitor a respiration parameter of the patient; 
 an inflation/deflation unit, comprising an interface connected to an inflation tube of the tracheal tube to inflate or deflate a cuff of the tracheal tube through the inflation tube; 
 an inflation/deflation control unit, connected to the inflation/deflation unit, to control the inflation/deflation unit to inflate and deflate the cuff so as to enable the cuff to meet an evaluation state; and 
 a data processing unit electrically connected to the respiration monitoring unit; 
 after an automatic airway status evaluation procedure to evaluate an airway patency is started:
 the inflation/deflation control unit is configured to automatically inflate and deflate the cuff, and 
 the data processing unit is configured to automatically: collect the respiration parameter of the patient from the respiration monitoring unit when the cuff is inflated and deflated to meet the evaluation state, evaluate an airway status of the patient according to the respiration parameter to obtain an evaluation result of the airway patency prior to extubation of the tracheal tube, and output the evaluation result to indicate whether the extubation can be performed. 
 
 
     
     
       7. The ventilator of  claim 6 , wherein the ventilator further comprises a pressure sensor, connected to the cuff, and a signal output end of the pressure sensor is electrically connected to the inflation/deflation control unit. 
     
     
       8. The ventilator of  claim 6 , wherein the respiration parameter monitored comprises any one of a tidal volume, a respiratory flow rate, an airway pressure, a carbon dioxide content, and a chemical indicator content. 
     
     
       9. The apparatus of  claim 1 , wherein the data processing unit generates graphic data displaying a visual representation of a pharynx of the patient with the tracheal tube inserted and outputs the graphic data to the ventilator, wherein the graphic data is changed according to different evaluation results of the airway status, and the changed graphic data in the visual representation include at least one of a cuff state, an airway state, and a position relationship between the cuff and the airway, such that:
 in a first stage of a cuff leak test in which tidal volumes are measured in multiple cycles during cuff inflation, the visual representation is changed to depict the cuff in an inflated state; 
 in a second stage of the cuff leak test in which tidal volumes are measured in multiple cycles during cuff deflation, the visual representation is changed to depict the cuff in a deflated state; and 
 in a third stage of the cuff leak test, if at least one preset evaluation criterion is met, the visual representation is changed to depict the cuff in the inflated state indicating that the extubation may be performed, or, if the at least one preset evaluation criterion is not met, the visual representation is changed to depict the cuff in a collapsed state and/or that the airway is narrow indicating that the extubation may not be performed.